Process of retting flax.



, plants for the separation of the woody fibers PEDRO RIVA, 0E BUENOS AYRES, ARGENTINA.

PROCESS OF BETTING FLAX.

@TLWM.

Ito Drawing.

Patented Sept. a, rate.

To all whom it may concern:

Be it known that I, PEDRO RIVA, a subject of the King of Italy, and a resident of 343 B. Mitre street, Buenos Ayres, Argentina, have invented certain new and useful improvements in Processes for Betting Flax, of which the following is a specification.

The present invention relates to a novel process-for retting flax, which consists in extracting therefrom the vegetable fiber or cellulose by which process the preparation of the and the eleinination of the'viscous matter lying immediately beneath the bark, that is to say, the substance which in the natural state of the plant binds the bark with the cellulose or vegetable fiber, is carried out in a combined'way.

The most ancient process for rotting flax consists in maintaining the plants, previously dried and tied up into smaller or larger bundles, in stagnant water, until a kind of putrefaction sets in which gradually destroys the glutinous matter. Another of the rural methods of retting flax is carried out by spraying the same; in accordance with this latter process the flax is extended on the ground and is left to the action of the atmos phere, and more or less frequently sprayed with water, according to the temperature of the season wherein said operation is eflected. These two methods of retting flax require a very long time, and are besides unhealthy, on account of the gases developed by putrefaction which infect the water, or the emanations which vitiate the atmosphere.

Inorder to avoid the above drawbacks, after many experiments made for rettin flax with chemical substances (such as pro acts of potash and sulfur), a method of retting by means of hot water has been adopted, which method was first introduced into Ireland by Schenck, while Watt and Buchanan invented the method of retting flax by means of boiling water The novel rooess which forms the subject matter 0? the present invention is superior to all other known methods, and its.

. half an hour, the

object is to shorten to a considerable degree the time required for this operation, and to. render the resulting fiber more tenacious and flexible and more susceptible of being bleached.

The retting process in accordance with my invention is carried out in the following way :The flax previously dried is subjected to the action with or without pressure of a suliicient volume of sulfurous water of a smaller or larger percentage of sulfur, according to the quality of the flax to be treated. I use water containing one fourth to one per cent. of sulfuric acid. It is then allowed to stand long enough to allow the sulfurous water to properly act upon the flax. The

acidulated water is allowed to stand long enough to properly act upon the flax and is then removed and the flax is subjected to the action of a vacuum, the object of which is to open' the flux and extract as far as possible the acidulated water or moisture. After- Ward the'fiax is subjected to the action with or withoutpressure of a sufficient volume of lye of soda or potash, which is again allowed to stand long enough to permit of the lye properly acting upon the flax. The lye is hen removed and the flax again subjected to the action of a vacuum which finishes the opening up of the flax. When this has taken place, the flax is finally subjected-to the ac tion of steam under pressure of different atmospheres, the object being to thoroughlv cleanse the flax from the substances with which it has been treated and other foreign matter. The steam treatment may last about ressure being 4 to 6 atmospheres. This last step completes my process.

What I claim is A. process for rettin flax, consisting in subjecting the flax to t e action of sulfurous water, then drawing off the water, then subjecting the flax to a vacuum, and finallysubjecting the flax to the action of steam 

